Since the early 1900s, when Bakelite was introduced into our homes, plastic has evolved spectacularly: from furniture to footwear to food packaging, we are now surrounded by the stuff.

But as it’s developed, it’s become a thorn in our side: In the UK alone, we produce over six million tonnes a year, half of which ends up in landfill and takes thousands of years to break down. And although recycling plastic works, it can require more energy than using virgin plastic, especially when it has been contaminated. Collecting it from householders is also a problem, but that’s another story.

So, when bioplastic hit the scene, externally indistinguishable from regular plastics and with the same end-of-life options, but with the potential to break down in much less time, it was an immediate hit.

Consisting of natural, plant-derived polymers from maize, sugarcane, wheat and corn, in the right conditions, with the help of naturally occurring microorganisms, bioplastics will break down to nothing but carbon dioxide and water. How long it takes depends on temperature, polymer stability and oxygen availability. However, an agreed standard, EN13432, defines how quickly and to what extent a material must degrade under commercial composting conditions for it to be ‘biodegradable’. Petroleum-based degradable plastics, which contain a metal additive to promote degradation, do not meet the EN standard.

The main bioplastics with multiple applications include: starch materials, which can absorb humidity and are used successfully for the production of drug capsules, for example; polylactic acid (PLA), produced from cane sugar or corn, which is transparent and resembles conventional Polyethylene (PE) or Polypropylene; cellulose materials; and Polyhydroxy fatty acids (PHA).

These bioplastics are said to have smaller CO2 footprints than conventional plastics, even though they still rely on petroleum to power farm machinery etc. Natureworks, a manufacturer of PLA, says it delivers a fossil fuel saving of ‘between 25 and 68 per cent compared with PE’.

With packaging representing a 35 per cent share in the plastic industry, producers have hungrily bought into bioplastics. Ever keen to be seen as green, supermarkets have embraced the new materials for their packaging. Elsewhere, mobile phone manufacturers such as Sony Ericsson, Samsung and NEC are experimenting with biodegradable plastic casings. There are even biodegradable nappies. In addition, the use of biodegradable cups, cutlery and the like can make all the waste associated with food at events compostable.

However, the rise of bioplastics has brought difficulties, some might say inevitably. The public, it seems, is opting for biodegradable whenever possible. But, with people eager to recycle everything and yet unable to differentiate between plastics, problems abound.

Just because these plastics are ‘biodegradable’, it doesn’t follow that you can discard them as you would nature’s own packaging and assume they will disappear on the compost heap. Bioplastic material landfilled without oxygen, light and water will not degrade quickly. And when it does, it emits methane.

Bioplastics should be sent to commercial composting facilities. But with a limited number around, this isn’t always possible. Indeed, Innocent Drinks was making its bottles from PLA, but has stopped due to the ‘lack of commercial composting in the UK’. An additional problem is that if any conventional plastic is found amongst compostable material, often the whole lot has to be landfilled. (This can happen even if the ‘plastic’ is biodegradable, as even the recycling operative cannot be sure of the difference.)

Add to the above the rising concern over food prices, which leads people to reconsider giving over hectares
of land to growing crops for packaging, and bioplastics are in trouble.

Peter Skelton, from WRAP’s Retail Team, is philosophical about the rise and fall of bioplastics: “Bioplastics are not bad materials per se, but there are many barriers to their greater use. One is its inability to be used across a range of applications. For example, using PLA to bottle drinks may not be ideal because of its relative poor barrier properties. Secondly, how they are disposed of is a problem. By composting the bioplastic you only get one use out of the material, whereas we know that PET can be recycled again and again to a product that is fit for food. At present, no one is reprocessing PLA to the same standard.” Skelton adds that bioplastics are currently small-scale and relatively expensive, but that “it is a young industry and it will evolve”.

So, where does that leave bioplastics? John Williams, from the National Non-Food Crops Centre (NNFCC), is disappointed by the backlash. “The problem is large multinationals jumped on the bandwagon before understanding the situation. Unfortunately, we don’t have the infrastructure in place in the UK to deal with bioplastics in the most effective way at the moment, but we will.

“Bioplastics can be disposed of through exactly the same routes as petroleum plastics. There is little evidence to suggest that the material produces any more methane than any other biowaste that goes to landfill currently.”

Indeed, according to Tony Breton, from Novamont, it is “essential that bioplastics are seen as part of a completely integrated supply system. It is quite dangerous to look at one part e.g. energy, water consumption, end-of-life, as you can find data to back or counter any argument, so you need to look at the whole system”.

Williams is equally frustrated by the land use argument. True, about 200,000 tonnes of bioplastics were produced last year from between 250,000 and 350,000 tonnes of crops, but Williams projects that the effect on land use is negligible. “Forty five per cent of starch production already goes into something other than food, so it’s just a case of scaling up. In fact, in Brazil, they already have an excess of sugar because of people’s changing lifestyles, so that’s why they’ve looked into bioplastic production – to ensure the sugar isn’t wasted.

“Bioplastics manufacturing remains relatively small. The problem is that it gets melded with biofuel, but doesn’t require even half as many crops.”

The Bioplastics Recycling Consortium, launched in August, is focussing on developing a recovery system and end markets for post-consumer bioplastics. “Packaging born of renewable material, then recycled and reused for new packaging is the ultimate definition of sustainability,” said Tim Ronan, vice president of marketing for Primo To Go, a company that bottles water in bioplastics. “Now is the time to seize in the life cycle opportunities that non oil-based bioplastics offer.”

However, Skelton suggests that bioplastics should not be the sole priority: “Last year the packaging industry used two million tonnes of plastics. Bioplastics made up just one per cent of that total. Rather than focussing on bioplastics, we need to look at how to deal with the millions of conventional plastics we use each year.”

Williams, on the other hand, is certain that bioplastics can be part of the future. “In terms of tackling the plastic waste stream, we’re in early days.
The closed loop system for PET bottles has only been developed in the last two years. There is still time to educate consumers about bioplastics.”

It’s clearly an emotive subject, but two things are clear: With the price of oil skyrocketing and landfills
no longer an easy option, the quest to find a sustainable answer to plastic continues.